Tian Yanqing, Fuller Emily, Klug Summer, Lee Fred, Su Fengyu, Zhang Liqiang, Chao Shih-Hui, Meldrum Deirdre R
Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, Tempe, AZ 85287-6501, USA.
Sens Actuators B Chem. 2013 Oct;188:1-10. doi: 10.1016/j.snb.2013.06.098.
A fluorescent colorimetric pH sensor was developed by a polymerization of a monomeric fluorescein based green emitter () with a monomeric 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran derived red emitter () in poly(2-hydroxyethyl methacrylate)--polyacrylamide (PHEMA-co-PAM) matrices. Polymerized () in the polymer matrices showed bright emissions at basic conditions and weak emissions at acidic conditions. Polymerized () in the polymer matrices exhibited a vastly different response when compared to . The emissions of are stronger under acidic conditions than those under basic conditions. When and were polymerized in the same polymer matrix, a dual emission sensor acting as a ratiometric pH sensor () was successfully developed. Because the and exhibited different pH responses and separated emission windows, the changes in the emission colors were clearly observed in their dual color sensor of , which changed emission colors dramatically from green at pH 7 to red at pH 4, which was detected visually and/or by using a color camera under an excitation of 488 nm. In addition to the development of the dual color ratiometric pH sensor, we also studied the effects of different matrix compositions, crosslinkers, and charges on the reporting capabilities of the sensors (sensitivity and p).
通过在聚（甲基丙烯酸2-羟乙酯）-聚丙烯酰胺（PHEMA-co-PAM）基质中，将基于单体荧光素的绿色发光体（）与单体2-二氰基亚甲基-3-氰基-4,5,5-三甲基-2,5-二氢呋喃衍生的红色发光体（）聚合，开发了一种荧光比色pH传感器。聚合的（）在聚合物基质中在碱性条件下显示明亮发射，在酸性条件下显示微弱发射。与相比，聚合在聚合物基质中的（）表现出截然不同的响应。在酸性条件下的发射比在碱性条件下更强。当和在同一聚合物基质中聚合时，成功开发了一种用作比率pH传感器（）的双发射传感器。由于和表现出不同的pH响应和分离的发射窗口，在其双颜色传感器中可以清楚地观察到发射颜色的变化，其发射颜色从pH 7时的绿色急剧变为pH 4时的红色，可通过视觉检测和/或在488 nm激发下使用彩色相机检测。除了开发双颜色比率pH传感器外，我们还研究了不同基质组成、交联剂和电荷对传感器报告能力（灵敏度和p）的影响。
